IRC log of tt on 2023-04-27

Timestamps are in UTC.

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logging to https://www.w3.org/2023/04/27-tt-irc
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RRSAgent, make logs Public
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Meeting: Timed Text Working Group Teleconference
15:02:08 [nigel]
Present: Eric, Gary, Chris, Nigel, Cyril, Andreas
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Chair: Gary, Nigel
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scribe: nigel
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Previous meeting: https://www.w3.org/2023/04/13-tt-minutes.html
15:02:52 [nigel]
Agenda: https://github.com/w3c/ttwg/issues/249
15:03:08 [nigel]
Present+ Pierre
15:03:47 [nigel]
Present+ Chris_Flick
15:03:53 [nigel]
Present+ Chris_Needham
15:03:58 [nigel]
Present- Chris
15:04:18 [nigel]
Topic: This Meeting
15:04:49 [nigel]
Nigel: On the agenda today we have DAPT, IMSC-HRM CR,
15:05:03 [nigel]
.. WebVTT#512 (metadata)
15:05:05 [Eric]
Eric has joined #tt
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.. and TPAC 2023 planning
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.. Any other business or things to make sure we cover?
15:05:35 [nigel]
no other business
15:05:54 [nigel]
.. Anyone want to switch the order around?
15:06:32 [nigel]
Present+ James
15:06:43 [nigel]
no order changes
15:06:44 [nigel]
Topic: DAPT
15:07:05 [nigel]
Nigel: We published FPWD, thank you everyone
15:07:06 [cpn]
scribe+ cpn
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-> FPWD published at https://www.w3.org/TR/2023/WD-dapt-20230425/
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present+
15:07:24 [nigel]
-> Blog post at https://www.w3.org/blog/news/archives/9896
15:07:44 [jcraig]
rrsagent, make minutes
15:07:46 [RRSAgent]
I have made the request to generate https://www.w3.org/2023/04/27-tt-minutes.html jcraig
15:07:53 [cpn]
Nigel: Some open issues to address
15:08:31 [cpn]
... Atsushi is setting up auto-publication
15:08:42 [cpn]
... We'll need to request horizontal and wide review, and address any comments
15:09:02 [cpn]
... Shall I rebase open pull requests?
15:09:12 [cpn]
Cyril: Feel free to do it now, or I can next week
15:09:32 [cpn]
Nigel: Anything else to say on DAPT?
15:10:01 [cpn_]
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scribe+ cpn_
15:10:09 [cpn_]
Topic: IMSC HRM
15:10:29 [cpn_]
Nigel: TAG review has been open a long time. I messaged Amy and Hadley to find out what's happening
15:11:16 [cpn_]
... We also need to sort out CR exit criteria. I proposed a change, want to make sure we think about it properly, given the charter changes
15:11:34 [cpn_]
... [reads current text]
15:11:45 [cpn_]
... I think one of each should be enough, without needing two of one
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... Either one content-producing implementation and one validating implementation or @@
15:12:38 [cpn_]
Pierre: I think that's a reasonable change
15:12:42 [nigel]
q?
15:13:21 [cpn_]
Nigel: So let's go with that, in absence of TAG review
15:13:29 [cpn_]
Pierre: I'd like to get a date for CR
15:13:46 [cpn_]
Nigel: I suggested 8 weeks after publication
15:14:25 [cpn_]
Pierre: As soon as we agree to publish, someone will modify it to reflect the actual publication date
15:14:37 [cpn_]
Nigel: A feature request for respec?
15:14:48 [cpn_]
... Anything else on IMSC HRM?
15:15:04 [cpn_]
Pierre: Should I ask Atsushi to pick a publication date, do we need a CfC?
15:15:21 [cpn_]
Nigel: We will, but nervous about doing that without TAG review, as they're a horizontal review group
15:15:36 [cpn_]
Pierre: They had comments, suggesting to make it a note
15:15:46 [cpn_]
Nigel: I disagreed with that, then discussion stopped
15:15:56 [cpn_]
Gary: They asked for clarification on what specifically needed review
15:16:02 [cpn_]
Nigel: I replied to that in the issue
15:16:17 [cpn_]
Gary: On making it a note is more of a personal thought than a TAG consensus
15:16:21 [nigel]
Present+ Eryk_Vershen
15:16:23 [cpn_]
Nigel: I think so
15:17:22 [cpn_]
Pierre: What's the right process? We can demonstrate review, let's say we're about to go to CR, set a date for them to do something
15:17:54 [cpn_]
Nigel: This discussion is enough for me to go back to TAG, to say we're being held up
15:18:12 [cpn_]
Pierre: Having a date makes it more concrete
15:18:32 [cpn_]
Nigel: May 16?
15:18:36 [cpn_]
Pierre: Sounds good
15:18:52 [cpn_]
Nigel: Any more on this topic?
15:18:59 [cpn_]
(nothing)
15:19:12 [cpn_]
Topic: WebVTT issue 512
15:19:42 [nigel]
github: https://github.com/w3c/webvtt/issues/512
15:20:02 [nigel]
jcraig: There seems to be a negative response to #511, so should we close that?
15:20:13 [nigel]
.. This is on the ambiguity of metadata, and there being no path to know
15:20:17 [nigel]
.. if it is metadata or a caption.
15:20:29 [nigel]
.. I suggested either a JSON block or a URI, but others are using other types of metadata
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.. so it is not always clear
15:20:37 [nigel]
q?
15:20:55 [nigel]
cpn_: I'm wondering what other alternative options for signalling the format we could think of.
15:21:12 [nigel]
Gary: I suggested a Metadata block akin to the Region block, should be backwards compatible.
15:21:23 [nigel]
.. I haven't tested that, but generally WebVTT says to ignore stuff you don't know about.
15:21:29 [nigel]
.. My main concern is backwards compat
15:21:41 [nigel]
.. General idea of having an in-file signal for the type of file is a valid request
15:22:02 [nigel]
jcraig: OK, I'll leave that one open and Eric and I will look into it more.
15:22:18 [nigel]
Gary: Do you want to give an overview of this proposal?
15:23:01 [nigel]
jcraig: Sure. [shares screen showing issue]
15:23:20 [nigel]
.. A few weeks ago Apple released the ability for Apple hardware devices like a Mac, AppleTV or iOS device
15:23:35 [nigel]
.. to automatically dim the screen by looking a few frames ahead at the flash patterns.
15:23:48 [nigel]
.. We released an open source library for this on GitHub as well.
15:23:59 [nigel]
.. The idea is to help anyone who has a negative reaction to the flashing,
15:24:10 [nigel]
.. as an alternative to only having a content warning.
15:24:22 [nigel]
.. We'd like to timecode where the flashing is.
15:24:37 [nigel]
.. We have an HLS proposal that Eryk V worked on. More information about that soon.
15:24:48 [nigel]
.. We would ideally like a way to specify the algorithm optionally.
15:25:01 [nigel]
.. In my VTT proposal it just says "level" without defining what that means.
15:25:19 [nigel]
.. If we were to include a test-uri and a test-version we could specify unambiguously what that level meant.
15:25:34 [nigel]
.. We could do a number of things with this, most obviously adjusting the timeline in some degree.
15:25:42 [nigel]
.. Like skipping over the flashes.
15:25:50 [nigel]
.. Thank you all who contributed to the discussion.
15:26:12 [nigel]
.. It seems like the general consensus is to not use WebVTT for this.
15:26:16 [cpn_]
q+
15:26:26 [nigel]
.. I'm not as familiar with WebVMT - Eric might want to add more context.
15:26:31 [nigel]
.. Happy to try to answer any more questions.
15:26:43 [nigel]
.. I know there were some HLS questions in the channel that haven't been answered yet.
15:26:48 [nigel]
ack cp
15:27:08 [nigel]
cpn_: WebVTT in terms of metadata is completely generic, and does not define any semantics
15:27:28 [nigel]
.. about metadata. WebVMT is an example for synchronising location and orientation data with video media.
15:27:38 [nigel]
.. It's a standalone specification that builds on top of WebVTT,
15:27:49 [nigel]
.. and defines the JSON object carried in the VTT file and its semantic.
15:28:00 [nigel]
.. The approach is to define it in its own specification as an application
15:28:07 [nigel]
.. rather than being in the WebVTT spec itself.
15:28:22 [nigel]
Gary: Yes, WebVMT also is a bit of a fork because it adds extra features to WebVTT.
15:28:32 [nigel]
.. If we go that route this metadata format would be simpler because it would not need
15:28:44 [nigel]
.. to redefine what WebVTT already defines, it would point to them directly.
15:28:59 [nigel]
q+
15:29:13 [nigel]
Gary: I was asking about how it would be represented in HLS.
15:29:44 [nigel]
.. How do you put it in the manifest, and how do you represent it in the TextTracks object.
15:30:13 [nigel]
Eryk: We use the DATERANGE tag in HLS. For conveying this data we have a specific class
15:30:19 [nigel]
.. and an added attribute that denotes the risk.
15:30:26 [nigel]
.. That's it, in the multi-variant playlist.
15:30:40 [nigel]
jcraig: And the class mentioned is more or less the same as the type value.
15:30:48 [nigel]
Eryk: Yes, it's a little more verbose.
15:31:00 [nigel]
Gary: So the HLS wouldn't be a segmented version of this WebVTT?
15:31:04 [nigel]
jcraig: It's different.
15:31:08 [nigel]
Gary: That sounds fine.
15:31:25 [nigel]
jcraig: The similarity is the timecode and the level - the type would be equivalent but not the same.
15:31:46 [nigel]
.. We chose that because general flash and red flash definitions are common in WCAG so we could expand
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.. it to that pattern.
15:32:04 [nigel]
Gary: It's exposed how HLS and Safari expose DATERANGE on the video element?
15:32:14 [nigel]
Eric: We expose DATERANGE as a data cue
15:32:22 [nigel]
Gary: That answers my questions.
15:32:27 [jcraig]
q?
15:32:43 [cpn_]
Nigel: Is this an Apple only feature, are other implementers interested?
15:33:12 [cpn_]
James: We hope others will be interested, users seem to be excited about it, so we'd like to have other platforms benefit from the idea
15:33:40 [cpn_]
... And we'd like to enable it for Apple's services on other platforms, Android apps and TV+ content for Samsung TVs etc
15:33:57 [cpn_]
Eryk: We'll be publishing it at the developers conference
15:34:10 [atai]
q+
15:34:30 [cpn_]
Nigel: I'm supportive of the idea it should be a separate spec. A good approach could be to draft a spec for this, and try to get support
15:34:42 [cpn_]
... Consider whether it's a Rec track document or a Note
15:34:53 [cpn_]
James: I'd defer to Eric or any of you on that
15:35:12 [cpn_]
Eric: Not sure there's a benefit to it being on the Rec track, it's more work, and may not be a benefit to anyone else
15:35:24 [cpn_]
Nigel: There's a lower bar for publishing a Note
15:35:58 [cpn_]
... A Note isn't normative, it doesn't carry any imprimatur of W3C as a whole, it's a document that people may find useful
15:36:18 [cpn_]
... We've used it for things that look normative, but things useful for industry more than things that are a recommendation
15:37:11 [cpn_]
James: Would a Note be a link to an external document?
15:37:30 [nigel]
cpn_: A Note is its own document rather than a note within a different document.
15:37:38 [nigel]
jcraig: Yes. It's a W3C Document type
15:38:18 [jcraig]
q+ EricC
15:38:23 [nigel]
Gary: You can't reference a Note normatively from a Rec
15:38:37 [cpn_]
q+
15:38:47 [nigel]
Nigel: The status of the document on a Note will say nobody should reference it normatively.
15:38:49 [nigel]
ack nigel
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ack atai
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q+
15:39:09 [nigel]
Andreas: That's definitely a good activity that I would support.
15:39:22 [nigel]
.. More generic question. We're discussing the syntax and the transport container.
15:39:30 [nigel]
.. Is there any more thought about a generic semantic model
15:39:35 [nigel]
.. that could be used for other formats.
15:39:47 [nigel]
.. Is the model already there? Or would it be useful to define it in a way that
15:39:53 [nigel]
.. could be used in other syntaxes or containers?
15:39:58 [nigel]
Gary: Like in IMSC?
15:40:02 [nigel]
Andreas: Yes
15:40:18 [nigel]
Eric: Do you mean specifically this kind of metadata or more generically to define a way to be able
15:40:26 [nigel]
.. to have other types of metadata in a VTT file?
15:40:32 [nigel]
Andreas: This specific flashing metadata
15:40:36 [nigel]
q?
15:40:49 [nigel]
jcraig: I'm not sure I fully understood that
15:41:10 [nigel]
.. We can dig into that
15:41:20 [nigel]
Andreas: It's independent of format, it's just a thought that this kind of information
15:41:32 [nigel]
.. would be structured specifically somewhere so it could be used regardless of format.
15:41:39 [nigel]
.. The semantics and expected behaviour could be similar.
15:41:51 [nigel]
jcraig: The data itself is not so complex that it would be difficult to do that transformation into other formats.
15:41:59 [nigel]
.. We're using it a different way in HLS.
15:42:17 [nigel]
.. I'm not opposed to a reusable structured format, that e.g. MPEG DASH could choose to implement,
15:42:33 [nigel]
.. using a format that this group defines, say, but I would not want a requirement to have a pass-through
15:42:46 [nigel]
.. format that would need to be supported. If we did want that we would need a Rec track document.
15:42:55 [nigel]
.. But a JSON block that can be used elsewhere, I'm all for that.
15:43:13 [nigel]
Eric: Or is the suggestion more to have a document that defines a value range, the elements of the metadata
15:43:29 [nigel]
.. so that in this case we could use it in JSON form, but it could also be used in XML form, pointing
15:43:37 [nigel]
.. back to a document that defines how to interpret them.
15:43:48 [nigel]
Andreas: Yes, thank you that's exactly what I had in mind.
15:44:01 [nigel]
jcraig: Seems reasonable to me. I don't think value should be defined in the transfer format
15:44:12 [nigel]
.. because it will be different depending on the algorithm that's used.
15:44:29 [nigel]
.. Apple's general flash algorithm outperforms Harding in some specific ways.
15:44:44 [nigel]
.. I could see there being multiple tracks, one using Harding, one the Apple open source algorithm,
15:44:50 [nigel]
.. another some other algorithm.
15:44:58 [nigel]
.. It's unlikely that anyone would ship all three.
15:45:06 [nigel]
.. The algorithm would define it, not the transport format.
15:45:08 [nigel]
q?
15:45:18 [nigel]
EricC: Do we have a document that defines these things for our new algorithm?
15:45:26 [Eric]
q-
15:45:35 [nigel]
ack Eric
15:45:51 [nigel]
Eric: If we do write up a Note or a Rec track document I don't think it needs to mention WebVMT.
15:45:57 [nigel]
.. It is just another type of metadata track.
15:46:12 [jcraig]
OSS project https://github.com/apple/VideoFlashingReduction/
15:46:33 [nigel]
jcraig: Posting some links here. The above is an algorithm.
15:46:56 [nigel]
.. There are also ePubs and PDFs that explain more, the first two links on the Whats New page:
15:46:59 [jcraig]
https://developer.apple.com/accessibility/#whats-new
15:47:06 [nigel]
-> https://developer.apple.com/accessibility/#whats-new What's New Page
15:47:24 [nigel]
jcraig: The ePub embeds a video.
15:47:25 [nigel]
q?
15:47:30 [nigel]
ack cpn_
15:47:41 [nigel]
cpn_: Coming back to the Note/Rec track question.
15:47:54 [nigel]
.. If this does become something more widely adopted across implementations,
15:47:56 [jcraig]
Those are also linked in Issue 512
15:48:04 [nigel]
.. is there anything that prevents a Note from being promoted to the Rec track?
15:48:17 [nigel]
.. Once there are multiple implementations you would want the benefits of a Rec track.
15:48:30 [nigel]
jcraig: I can't think of anything that would prevent us from promoting a Note to a Rec
15:48:39 [nigel]
Nigel: Are there any IPR considerations here?
15:48:50 [nigel]
jcraig: Good question, I will have to get back to you on that one.
15:49:08 [nigel]
.. We did an IPR review before I posted this issue and the algorithm and open source project.
15:49:23 [nigel]
.. If it were within the TTWG it would be covered by the W3C patent policy.
15:49:53 [nigel]
Pierre: Whatever is submitted to this group (by members) is subject to the IPR policy.
15:50:00 [nigel]
.. There's an exclusion that starts with the FPWD.
15:50:30 [gkatsev]
q?
15:50:36 [jcraig]
ack p
15:50:41 [nigel]
.. I've never heard that publishing a Note relaxes the constraints for a Rec track.
15:50:58 [nigel]
.. At a high level, a WG Note is a WG decision, really. The consensus body and review will be a lot
15:51:04 [nigel]
.. narrower than for a Rec track document.
15:51:13 [nigel]
.. You'll get much less attention, and there will be a lot less overhead.
15:51:26 [jcraig]
s/TTWG it would be covered by the W3C patent policy./TTWG I think it would be covered by the W3C patent policy, but I will take a note to follow up internally./
15:51:37 [nigel]
.. We talked about IPR. Typically, what I've mostly seen in Notes is application of existing standards
15:52:02 [nigel]
.. Something with its own applications, process and technology is typically better as a Rec track document.
15:52:10 [nigel]
.. I don't have a strong opinion, just trying to answer the question.
15:52:24 [nigel]
jcraig: Maybe the alternative is to take this as an incubator and not decide on Note or Rec track until
15:52:28 [nigel]
.. later in the process.
15:52:41 [nigel]
.. We can publish in WICG and bring into TTWG if that's the appropriate place for it to land.
15:52:47 [nigel]
Pierre: That's true too.
15:53:35 [cpn_]
Nigel: WICG isn't the only place to incubate, can do in WG or another CG
15:53:47 [cpn_]
... We have a broad charter in terms of applications of timed text
15:54:09 [cpn_]
James: Easier for us to participate where other organisations have joined already
15:54:35 [cpn_]
Nigel: Publishing a Note in a WG is a bit like an incubation
15:55:35 [cpn_]
James: My typical process in WICG is write in a wiki page, hence a reason to prefer that. The other benefit is you get people who are just interested in the one topic, which helps with organising meetings
15:55:55 [cpn_]
Nigel: Any final thoughts on this topic?
15:56:05 [cpn_]
James: Thank you all
15:56:43 [nigel]
SUMMARY: Apple to think about next steps for incubation
15:56:43 [cpn_]
Nigel: In summary, Apple to think about next steps for incubation
15:56:43 [nigel]
Topic: TPAC 2023 planning
15:57:17 [nigel]
Gary: I did not submit the questionnaire yet. We have some time.
15:57:30 [nigel]
.. My main question is: we want to do the joint meetings with MEIG and MediaWG.
15:57:38 [nigel]
.. How much time do we want for TTWG itself?
15:57:50 [nigel]
.. I think we're probably more constrained because of the overlap with IBC.
15:58:34 [nigel]
Nigel: I would propose we allocate no more than 1 day for TTWG, which
15:58:46 [nigel]
.. could include joint meetings, and try to be efficient in the time that we get.
15:58:57 [nigel]
.. We normally go for 2 days but that's difficult for some.
15:59:14 [nigel]
cpn_: Would you want one joint meeting with MEIG and MediaWG or two separate joint meetings?
15:59:29 [nigel]
Gary: I'm not sure. One of the agenda topics we're thinking about is the TextTrack API, so having
15:59:35 [nigel]
.. the Media WG would be worth it there.
15:59:44 [nigel]
Nigel: Works for me.
15:59:57 [nigel]
cpn_: Sounds good. For MEIG I'm proposing we do a morning, and then have
16:00:02 [nigel]
.. agenda time allocated within that block.
16:00:16 [nigel]
.. I'm concerned that we request enough timeslots in the overall schedule so
16:00:29 [jcraig]
s/general flash and red flash definitions/general flash, red flash, and spatial pattern definitions/
16:00:31 [nigel]
.. the MediaWG joint meeting can be a dedicated session. Then if needed we can have time in the MEIG
16:00:40 [nigel]
.. session for any TTWG relevant agenda topics.
16:01:47 [jcraig]
s/James: Would a Note be a link to an external document?/??? maybe ChristopherF?: Would a Note be a link to an external document?/
16:01:51 [nigel]
Topic: Meeting close
16:02:02 [nigel]
Nigel: We're out of time for today. Thanks everyone, next call in 2 weeks.
16:02:29 [nigel]
.. Thanks to those who attend less often but came today - you're always welcome.
16:02:35 [nigel]
.. [adjourns meeting]
16:02:39 [nigel]
rrsagent, make minutes
16:02:41 [RRSAgent]
I have made the request to generate https://www.w3.org/2023/04/27-tt-minutes.html nigel
16:03:45 [jcraig]
s/Apple's general flash algorithm outperforms/we think Apple's general flash algorithm outperforms/
16:04:08 [nigel]
s/.. Anyone want to switch the order around?/Nigel: Anyone want to switch the order around?
16:04:37 [nigel]
s/FPWD published at/FPWD
16:04:51 [nigel]
s/Blog post at/W3C Blog post
16:05:34 [nigel]
s/Either one content-producing implementation and one validating implementation or @@/Either one content-producing implementation and one validating implementation or two validating implementations
16:06:07 [nigel]
s/A feature request for respec?/A feature request for respec to specify relative dates? I might suggest that!
16:06:09 [jcraig]
s/It's unlikely that anyone would ship all three./Though perhaps it's unlikely that a media publisher would want to support all three for and specific video. [Update: more likely when it is fully automated.]/
16:07:05 [nigel]
s/cpn_/Chris_Needham/g
16:07:15 [nigel]
s/jcraig/James_Craig/g
16:08:23 [jcraig]
rrsagent, make minutes
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I have made the request to generate https://www.w3.org/2023/04/27-tt-minutes.html jcraig
16:11:06 [nigel]
s/James_Craig/James/g
16:11:52 [nigel]
s/EricC/Eric/g
16:12:35 [nigel]
s/What's New Page/Apple Accessibility What's New Page
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rrsagent, make minutes
16:13:50 [RRSAgent]
I have made the request to generate https://www.w3.org/2023/04/27-tt-minutes.html nigel
16:14:32 [nigel]
Present- jcraig
16:14:37 [nigel]
rrsagent, make minutes
16:14:39 [RRSAgent]
I have made the request to generate https://www.w3.org/2023/04/27-tt-minutes.html nigel
16:15:43 [nigel]
s/Nigel: In summary, Apple to think about next steps for incubation//
16:15:52 [nigel]
scribeOptions: -final -noEmbedDiagnostics
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rrsagent, make minutes
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I have made the request to generate https://www.w3.org/2023/04/27-tt-minutes.html nigel
16:17:12 [nigel]
Regrets: Atsushi
16:17:12 [nigel]
rrsagent, make minutes
16:17:14 [RRSAgent]
I have made the request to generate https://www.w3.org/2023/04/27-tt-minutes.html nigel
16:20:17 [nigel]
zakim, end meeting
16:20:17 [Zakim]
As of this point the attendees have been Eric, Gary, Chris, Nigel, Cyril, Andreas, Pierre, Chris_Flick, Chris_Needham, James, jcraig, Eryk_Vershen
16:20:19 [Zakim]
RRSAgent, please draft minutes v2
16:20:20 [RRSAgent]
I have made the request to generate https://www.w3.org/2023/04/27-tt-minutes.html Zakim
16:20:26 [Zakim]
I am happy to have been of service, nigel; please remember to excuse RRSAgent. Goodbye
16:20:26 [nigel]
rrsagent, excuse us
16:20:26 [RRSAgent]
I see no action items
16:20:27 [Zakim]
Zakim has left #tt